#region Copyright (c) 2007 Ryan Williams <drcforbin@gmail.com>
/// <copyright>
/// Copyright (c) 2007 Ryan Williams <drcforbin@gmail.com>
/// 
/// Permission is hereby granted, free of charge, to any person obtaining a copy
/// of this software and associated documentation files (the "Software"), to deal
/// in the Software without restriction, including without limitation the rights
/// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
/// copies of the Software, and to permit persons to whom the Software is
/// furnished to do so, subject to the following conditions:
/// 
/// The above copyright notice and this permission notice shall be included in
/// all copies or substantial portions of the Software.
/// 
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
/// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
/// THE SOFTWARE.
/// </copyright>
#endregion

using System;
using System.IO;
using System.Collections.Generic;
using System.Text;

using Mono.Cecil;

namespace Obfuscar
{
	class AssemblyCache
	{
		private readonly Project project;

		private readonly Dictionary<string, AssemblyDefinition> cache =
			new Dictionary<string, AssemblyDefinition>( );
		private readonly IAssemblyResolver resolver = new DefaultAssemblyResolver( );

		public AssemblyCache( Project project )
		{
			this.project = project;
		}

		private AssemblyDefinition SelfResolve( AssemblyNameReference name )
		{
			AssemblyDefinition assmDef;
			if ( !cache.TryGetValue( name.FullName, out assmDef ) )
			{
				assmDef = null;

				string[] exts = new string[] { ".dll", ".exe" };

				foreach ( string ext in exts )
				{
					string file = Path.Combine( project.Settings.InPath, name.Name + ext );
					if ( File.Exists( file ) )
					{
						assmDef = AssemblyFactory.GetAssembly( file );
						cache[name.FullName] = assmDef;
						break;
					}
				}
			}

			return assmDef;
		}

		public TypeDefinition GetTypeDefinition( TypeReference type )
		{
			if ( type == null )
				return null;

			TypeDefinition typeDef = type as TypeDefinition;
			if ( typeDef == null )
			{
				AssemblyNameReference name = type.Scope as AssemblyNameReference;
				if ( name != null )
				{
					// try to self resolve, fall back to default resolver
					AssemblyDefinition assmDef = null;
					assmDef = SelfResolve( name );
					if ( assmDef == null )
					{
						try
						{
							assmDef = resolver.Resolve( name );
							cache[name.FullName] = assmDef;
						}
						catch ( FileNotFoundException )
						{
							throw new ApplicationException( "Unable to resolve dependency:  " + name.Name );
						}
					}

					string fullName = type.Namespace + "." + type.Name;
					typeDef = assmDef.MainModule.Types[fullName];
				}
			}

			return typeDef;
		}
	}
}
